Phosphino-s-triazines



United States Patent 3,213,093 PHOSPHINO-s-TRIAZINES Grace Peters Pappand Sheldon A. Buckler, Stamford, Conn., assignors to American CyanamidCompany, Stamford, Conn., a corporation of Maine No Drawing. Filed Dec.12, 1963, Ser. No. 329,964 6 Claims. (Cl. 260-249.8)

The present invention relates to monosubstituted phosphino-s-triazines,disubstituted phosphino-s-triazines, and their oxides. Moreparticularly, the instant discovery concerns a novel method forpreparing a novel class of compounds which comprises reacting an alkalimetal salt of an organic phosphine with a substituted or unsubstitutedchloro-s-triazine in an appropriate solvent. The following equation isgeneric:

wherein R and R each represent alkyl (C -C cyclopentyl, cyclohexyl,phenyl, lower alkyl-substituted phenyl, H and naphthyl; X and X eachrepresent chloro, bromo, lower alkyl, phenyl, amino, monoand di-alkyl (C-C substituted amino and mono-cyclohexylamine;

M is alkali metal, i.e., Na, K, Li; and n is selected from 0 and 1.

Preferably, an inert organic solvent is employed. Typical solvents arecyclic ethers, such as dioxane, tetrahydrofuran (THF), and the like,non-cyclic ethers, such as diethyl ether, dibutyl ether, and othersolvents which under the conditions of the reaction to be described,infra, will not react to any substantial degree with the reactants orthe desired reaction products. Acetonitrile is another typical solvent.

Reaction is best carried out at a temperature in the range of 0 C. to150 C., preferably 20 C. to 90 C. or at the reflux temperature of thesolvent employed. While equimolar amounts of the reactants are generallyemployed, an excess of either reactant with respect to the other may bepresent.

Generally the oxide product described in the generic formula hereinaboveresults when the reactants and/or products thereof are exposed to air oroxygen during the reaction, during isolation of the reaction products orsubsequent to recovery of the desired reaction product.

The novel products of the present invention are flame proofing agents.For example, cotton fabric, such as cotton cloth, dipped into a suitablesolvent containing up to about 10% by weight of any one of the novelcompounds prepared herein exhibit, upon drying, very desirableresistance to flaming when contacted with an open flame.

The present invention will best be understood from the followingexamples which are intended to be illustrative and not to unduly limitthe scope of the present invention, excepting of course as suchlimitations appear in the appended claims.

3,213,093 Patented Oct. 19, 1965 EXAMPLE I 2- [4,6-bis-(dimethylamino)-s-triazinyl]-diphenylphosphine oxide A slurry of sodiumdiphenylphosphide in dioxane is prepared from 5.5 grams (0.025 mole) ofdiphenylchlorophosphine by refluxing 4 hours with excess sodium (2.4grams, 0.1 mole) in 50 cubic centimeters of dry dioxane. Upon cooling,excess sodium is removed, the product remaining as a yellow solid,together with by-product NaCl. To this slurry, 4.4 grams (0.022 mole) of2-chloro-4,6- bis (dimethylamino)-s-triazine is added, together with 15cubic centimeters of dioxane. The temperature rises from 25 C. to 33 C.as the yellow color is discharged. After 3.5 hours at reflux, theresulting mixture is cooled and filtered using Hyflo. Concentration ofthe filtrate under reduced pressure leaves a solid weighing 4.5 gramsafter a wash with hexane and having a melting point of 145 C.163 C.Recrystallization from 50% aqueous methanol and then aqueous acetonegives long needles having a melting point of 168 C.-171 C. Extraction ofthe inorganic salts with boiling methanol gives 2.1 grams of solublesolids from which 0.4 gram of additional product is obtained byrecrystallization from aqueous methanol and further precipitation withwater. Initial analysis indicates the product is slowly oxidizing to thephosphine oxide, so subsequently a portion of the original crude productis treated with an equivalent amount of 30% H 0 in methanol, heated atreflux for 3 hours and then diluted with water. The precipitated producthas a melting point of 171 C.173 C. from aqueous methanol and analyzescorrectly for 2-[4,6-bis(dimethylamino)-s-triazinyl]-diphenylphosphineoxide.

EXAMPLE II 2,4-bis(dimethylamin0) -6-dicycl0hexylphosphin0- s-triazineDicyclohexyl lithium phosphide is prepared by adding 10 grams (0.05mole) of dicyclohexylphosphine in 20 cubic centimeters of ether to asolution of phenyl lithium (0.1 mole) in cubic centimeters of etherfollowing the methods of Issleib and Tzschach, Berichte, 92, 1124(1959). (Phenyl lithium is prepared from 15.7 grams (0.1 mole) ofbromobenzene and 1.5 grams (0.22 gram atom) of lithium in 75 cubiccentimeters of ether.) A solid yellow phosphide separates within 25minutes. To this slurry 10 grams (0.05 mole) of2-chloro-4,6-bis(dimethylamino)-s-triazine in 50 cubic centimeters ofdioxane is added at 25 C. The resulting mixture is stirred 1 hour andallowed to stand overnight. Filtration gives 22.4 grams of solid, fromwhich 1.0 gram of product is obtained by extracting with benzene,evaporating and triturating with ethanol. Evaporation of thedioxaneether filtrate leaves 15 grams of brown smeary residue. Aftervarious attempts to induce crystallization, 12.6 grams of materialextracted by petroleum ether is dissolved in a minimum of CH CN toobtain another 1.0 gram of product, melting point 72 C.-75 C.Recrystallization from aqueous isopropanol gives 2,4-bis (dimethylamino)6 dicyclohexylphosphino s triazine, melting point 77 C.78 C. whichanalyzes as follows:

Calculated for N PC H C, 62.78; H, 9.43; N, 19.27; P, 8.52. Found: C,62.70; H, 9.14; N, 19.29; P, 8.40.

3 EXAMPLES Ill-XIII The following Table I further illustrates thepresent invention, each example therein being carried out essentially asin Example I or II, above, excepting as indicated;

phosphide) in dioxane is prepared according to the method of Issleib andKrech (Berichte 94, p. 2656, 1961).

This is then reacted With grams (0.1 mole) of 2-chloro- 4,6-bis(dimethylamino)-s-triazine as in Example I, above.

TABLE I N N it R\ x T01 x-F TP\ /PM L N N R MCI Example R NO )E, )L!

R B. M X X Solvent Temp., Reaction as in n X X R R M 0. Example N0.

III Ethyl Ethy K.-- Br Br. Diov'me IV Propyl K." 01 Eth TH]. 20 V exylHexyl Li, Methyl Methyl Diethyl ether VI Octyl Butyl Na Phenyl ClDioxane 25 VII-.-" Methyl K Ethy Ethy .....d0 25 1 VIII..-" Phenyl Na CNH2 Dibutyl ether. 1

CzHs

IX CyclohexyL. Cycl0hexyl Ne... N\ NH2 THF* 25 II 0 CzHs [X, X, R R andCaHr-z 19%, abov e, have esame mean- X Xylyl Fl" LL- NHz -N THE 30 II 0ings given them under reactant CsHn forn ilae (A)h an int is C12H25 Htable].

XI Naphthyl.-- H K.-- -N\ THF 25 I 1 H CaH YTT T01y1 Tolyl- Na C CDibutyl ether 110 II 0 XIII H Cyclopentyl.-- Na -N\ NH2 Diethyl ether 30II 0 'Tetrahydrofuran.

It has been further found, pursuant to the present invention, that achloro-s-triazine reactant of the type contemplated herein reacts withan alkylene bis(phenyllithiumphosphide) under the conditions givenhereinabove, to yield interesting bridged products having the same usesascribed to the product phosphino-s-triazines hereinabove described. Thereaction may be described generically as follows:

Conversion of the resulting product to its corresponding oxide iscompleted by treatment with an equivalent of 30% H 0 in methanol, alsoas in Example I, above, the product recovered beingethylenebis[[4,6-bis(dimethy1- amino)-s-triazin-2-yl]phenylphosphineoxide].

EXAMPLE XV 2,2'-[tctramethylenebis(pheny-lphosphinidene) bis[4,6-(diamino -s-!riazine] The reaction of 0.1 molar tetramethylenebis(phenyllithiumphosphide) with 0.2 mole (21.9 grams) ofZ-chloro-4,6-diamino-s-triazine is carried out as in Example XIV, above,except for oxidation with H 0 The product obtained is recrystallizedfrom methanol to obtain 2,2'-[tetramethylenebis(phenylphosphinidene)]bis [4,6 (diamino)- s-triazine] The reaction of Example XIV can berepeated in every essential respect using the triazine XI/NICI reactantsdescribed hereinabove, e.g., those of Examples IX, XI, XIII, etc., toyield the corresponding bridged diphosphine products of the Formula Dabove.

Clearly the instant discovery encompasses numerous modifications withinthe skill of the art. Consequently, while the present invention has beendescribed in detail with respect to specific embodiments thereof, it isnot intended that these details be construed as limitations upon thescope of the invention, except insofar as they appear in the appendedclaims.

We claim:

1. A compound of the formula wherein R and R each represent a memberselected from the group consisting of alky1(C -C cyclopentyl,cyclohexyl, phenyl, lower alkyl-substituted phenyl, naphthyl and H; Xand X each represent a member selected from the group consisting ofchloro, bromo, lower alkyl, phenyl, amino, monoand di-alkyl (C C)-substituted amino and mono-cyclohexylamine; and n is selected from 0and 1.

2. 2 [4,6 bis(dimethylamino)-s-triaziny1] diphenylphosphine oxide.

3. 2,4-bis(dimethylamino) 6 dicyclohexylphosphinos-triazine.

4. A compound of the formula References Cited by the Examiner UNITEDSTATES PATENTS 2,685,581 8/54 Coover 260248 3,064,055 11/62 Herring260461 OTHER REFERENCES Kosolapoff: Organophosphorus Compounds, JohnWiley and Sons, Inc., New York (1950), page 13.

Van Wazer: Phosphorus and Its Compounds, volume 1, Chemistry,Interscience Publishers, Inc., New York, 1958, page 123.

WALTER A. MODANCE, Primary Examiner.

NICHOLAS S. RIZZO, Examiner.

1. A COMPOUND OF THE FORMULA
 4. A COMPOUND OF THE FORMULA